1. Field of the Invention
The invention pertains to a device that uses suction to remove the contents from valve bags. The device comprises a bag support having flaps that hold the bag. A suction piece is inserted into the valve opening of the valve bag and the valve bag is rotated up to about 180° so that the valve opening is in a downward position. Suction draws product out of the bag. In this manner, the valve bag can be emptied without ripping the bag and product dusting is eliminated during product removal. The invention also pertains to a method for removing the contents of a valve bag by using suction.
2. The Related Art
Particulate materials are commonly packaged in bags that are made from multiple layers of paper and have a valve and valve opening in one upper corner. The valve provides an opening through which the material is dispensed during the bag filling operation. The valve bag is typically filled by inserting a spout or nozzle into the valve and causing material to flow through the nozzle into the bag. When the bag is full, the flow of material is halted and the nozzle is withdrawn from the valve usually by moving the bag away from the nozzle. The valve is closed to prevent egress of the material from the bag during shipping and handling. U.S. Pat. No. 4,550,755 describes a bag filling machine for valve bags.
The general method for removing the contents of a valve bag is to cut the bag and physically remove the contents of the bag through the cut opening. A bag cutting device is described in U.S. Pat. No. 4,627,781. Cutting the bag may undesirably result in contamination of the bag contents with non soluble residue fibers from the bag. Thus, a method for extracting product from valve bags that does not require cutting the valve bag would be welcomed in the art.
A system for using a siphoning nozzle to remove the contents from upright bulk bags is described in U.S. Pat. No. 5,975,351. U.S. Pat. No. 5,682,929 describes a system for the multiple filling and emptying of a receptacle with pourable product. The bags described in U.S. Pat. No. 5,682,929 have openings on the bottom for removing product from the bag with a suction hose wherein the discharging device has agitating fingers. U.S. Published Patent Application No. U.S. 2003/0006248 describes the use of a vacuum to remove the contents from a bulk bag to a hopper.
We have developed a device and method for efficiently removing the contents of a valve bag, preferably a bag having one valve opening, without requiring the undesirable ripping of the bag and unwanted dusting while removing product from the bag. The method and device uses flaps to secure the valve bag and a suction piece is inserted into the valve opening. The device rotates the valve bag up to about 180° and can rotate the valve bag as much as about 360°, so that the valve opening is pointing downward. Suction is used to remove the contents of the valve bag.
When the valve opening is in a downward position, the contents of the valve bag move towards the valve opening. This prevents significant aeration of the contents within the valve bag during removal, inhibits plug flow at the valve opening and prevents the bag materials from blocking the nozzle at the valve opening during the removal. Also, because the material within the valve bag flows downward during content removal, the valve bag during the operation collapses on the upper edge of the moving material, opposite to the valve opening, which results in a substantially collapsed bag after the removal process facilitating removal from the apparatus and disposal or recycling.